Large street lamp integrated PCB module with EMC anti-interference performance and high expansibility and control method

Abstract

The invention discloses a large street lamp integrated PCB module with EMC anti-interference performance and high expansibility and a control method, and belongs to the technical field of lighting equipment PCB design, electromagnetic compatibility and intelligent expansion, and the large street lamp integrated PCB module comprises eight layers of basic PCBs, two layers of stackable expansion PCBs and a board-to-board connector, after expansion, conducted disturbance and radiated disturbance both accord with related mandatory certification standards, the anti-interference capability is excellent, external interference such as electrostatic discharge and surge can be resisted, no abnormal reset condition exists in the hot plug process of the expansion interface, and stable electromagnetic compatibility is kept in the whole process; the expansibility and the scene adaptability are obviously improved; through the combination modes of the base and the PCB matched with different extensions and PCBs, the system can be flexibly adapted to various application scenes such as home use, office, outdoor and the like, and mold opening research and development do not need to be carried out again; the expansion interface is compatible with a general communication protocol, can adapt to market mainstream sensors and intelligent modules, and does not need customized development.

Description

Technical Field

[0001] This invention belongs to the fields of PCB design, electromagnetic compatibility and intelligent expansion technology for lighting equipment, specifically referring to an integrated PCB module and control method for streetlights that combines EMC anti-interference performance with high expandability. Background Technology

[0002] Existing integrated PCB modules for streetlights present a significant contradiction between EMC immunity and scalability, making it difficult to meet the flexible adaptation to multiple scenarios and stringent EMC requirements. Specific pain points are as follows:

[0003] Limited functional expansion and high risk of interference introduction: Traditional integrated PCBs lack standardized expansion interfaces. When adding functions such as environmental sensing, human body sensing, and emergency lighting, external modules need to be connected by flying wires, which not only damages the PCB integration but also easily introduces external interference.

[0004] Poor scene adaptability: PCBs need to be designed separately for scenarios such as home, office, and outdoor trails. High voltage / low voltage versions are not interchangeable, increasing mold and R&D costs by more than 40%. Weak intelligent expansion compatibility: Existing modules only support basic voice / remote control / APP three-mode control and cannot access intelligent functions such as AI dimming, Bluetooth Mesh networking, and NFC quick configuration. Moreover, when adding chips, their radiated noise can easily cause the original EMC performance to exceed the standard.

[0005] EMC Co-operation Failure After Expansion: When the multi-channel drive is expanded to more than 4 channels, the original filtering network cannot cover the new channels, resulting in EMI superposition between channels; the external expansion module has no dedicated shielding, and its radiated interference can easily lead to packet loss rate in WiFi communication. To address this, a street light integrated PCB module and control method with both EMC anti-interference performance and high scalability are proposed. Summary of the Invention

[0006] The purpose of this invention is to provide an integrated PCB module and control method for streetlights that combines EMC anti-interference performance with high scalability, in order to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a street light integrated PCB module and control method that combines EMC anti-interference performance with high scalability. The PCB module includes an 8-layer base PCB, a 2-layer stackable expansion PCB, and board-to-board connectors. The control method includes the following steps:

[0008] S1. After the PCB module is powered on, the SY8829 wide voltage PMIC on the basic PCB starts to adapt to wide voltage input. The MCU initializes the expansion module library and automatically identifies the connected AI, Bluetooth Mesh, sensor and other expansion modules, and loads the corresponding drivers.

[0009] S2, the global EMC filtering network starts up simultaneously, using the common mode inductor and X / Y capacitor of the basic PCB, the ferrite beads, TVS tubes and hierarchical shielding structure of the extended interface to suppress power grid interference, interface interference and radiation interference in multiple dimensions.

[0010] S3. When the extended function is running, the MCU dynamically adjusts parameters such as PWM spread frequency period and computing power allocation to achieve coordinated adaptation between the extended function and EMC performance.

[0011] S4. Depending on the application scenarios such as home, office, and outdoor, mode switching can be completed simply by replacing the appropriate expansion PCB, without the need to redesign the basic PCB.

[0012] S5. When multiple expansion modules work simultaneously, the MCU prioritizes allocating computing power to key EMC algorithms such as PWM spread spectrum and wireless frequency hopping to avoid EMI superposition.

[0013] S6. The wireless communication module monitors the channel interference intensity in real time and automatically switches to a low-interference backup channel to ensure communication stability.

[0014] S7. When a module overcurrent fault or emergency lighting requirement occurs, the corresponding protection mechanism will be activated to ensure that the core functions and EMC performance continue to meet the standards.

[0015] The 8-layer base PCB is stacked in a signal-ground-power-ground-signal-power-ground-signal configuration, divided into a high-voltage power supply area, a low-voltage control area, a wireless communication area, a 6-channel configurable driver area, and an expansion interface area. The expansion interface area has 4 sets of board-to-board connector pads, and ferrite beads, resettable fuses, and TVS diodes are installed next to the interfaces. The 2-layer stackable expansion PCB includes an expansion module area and a peripheral interface area. The expansion module area has 2 shielded sub-cavities, and the peripheral interface area is equipped with JSTPH2.0 terminals. The board-to-board connectors are 10-pin, with ground pins prioritized. The L4 layer of the base PCB is the main ground plane with a copper thickness of ≥2oz. The expansion channel ground and signal ground are connected through independent vias, and the ground loop impedance is ≤1Ω.

[0016] Preferably, the L5 layer of the 8-layer base PCB is a wide-voltage high-voltage layer, adopting an AC-CDC+DCDC dual-path design. The AC input is converted to DC12V through the SY8829 wide-voltage PMIC, and DC12-48V is directly connected. The two inputs are isolated from each other by diodes to avoid circuit damage. The L6 layer is a 6-channel configurable power supply layer, with a reserved 0Ω resistor voltage switching pad for each channel. The 12V, 24V, and 48V output voltages can be flexibly adapted by soldering 0Ω resistors. Each channel is connected in parallel with a 10μF electrolytic capacitor and a 0.1μF ceramic capacitor to form a decoupling circuit to suppress power ripple and ensure drive stability.

[0017] Preferably, the E1 layer of the two-layer stackable expandable PCB has two shielding sub-cavities with dimensions of 10mm×8mm×2mm, which respectively cover the AI ​​module and the Bluetooth Mesh module. The sidewalls of the shielding sub-cavities are made of 0.2mm thick copper foil, which is fixed to the ground plane of the E2 layer through vias. The top is covered with a 0.1mm thick copper cap, which is in contact with the sidewalls through conductive foam to ensure shielding effectiveness ≥35dB. The E2 layer is laid with JSTPH2.0 series terminals, including 2-pin terminals and 4-pin terminals, which are respectively adapted to the temperature and humidity sensor and the emergency lighting module. TVS diodes and 100pF filter capacitors are connected in parallel next to each terminal to suppress electrostatic and electromagnetic coupling interference.

[0018] Preferably, the horizontal distance between the expansion interface area and the core control area of ​​the basic PCB is greater than or equal to a preset threshold of ≥4mm, and the vertical direction is doubly isolated through the L2 signal ground and the L4 main ground plane to avoid noise coupling of the expansion module to the core control circuit; a 0.3mm thick copper foil shielding dam is provided around the expansion interface area, with a dam height of 1.5mm, and is connected to the L2 signal ground through 4 evenly distributed vias to form a closed interface shielding cover, and the signal line spacing inside the dam is ≥0.5mm to further suppress crosstalk between signal lines.

[0019] Preferably, in S1, the MCU model is GD32F103, and its firmware has a complete built-in expansion module library. The types of expansion modules that can be automatically identified include lightweight AI modules, Bluetooth Mesh modules, NFC configuration modules, temperature and humidity sensors, human body sensing modules, emergency lighting modules, etc. The identification process is achieved by detecting the communication pin signal characteristics of the expansion interface. The identification response time is ≤50ms. After successful identification, the corresponding driver program and filtering parameters are automatically loaded, such as the sensor sampling frequency is adapted to 1kHz to avoid interference caused by resonance with the PWM drive frequency.

[0020] Preferably, in S2, the full-area EMC filtering network is specifically configured as follows: the L8 layer of the basic PCB integrates a 10mH common-mode inductor, a 0.1μFX capacitor, and a 2200pFY capacitor to suppress conducted interference on the power grid side; each signal line in the extended interface area is connected in series with a ferrite bead to suppress high-frequency signal interference; the TVS diode next to the peripheral terminal on the E2 layer of the extended PCB can withstand ±15kV air discharge and ±8kV contact discharge to prevent electrostatic damage to the module; the hierarchical shielding structure includes primary shielding, secondary shielding, and tertiary shielding. The primary shielding is the shielding cavity of the core WiFi / voice module with a shielding effectiveness ≥40dB; the secondary shielding is the shielding sub-cavity of the extended AI / Bluetooth module; and the tertiary shielding is the dam surrounding the extended interface, achieving full-area EMC protection without dead angles.

[0021] Preferably, in S3, the implementation of the expansion function and EMC coordination is as follows: When the AI ​​module runs the adaptive dimming algorithm, the MCU dynamically adjusts the PWM spread frequency period from the basic 10ms to 8ms according to the computing power occupancy of the AI ​​module, ensuring dimming accuracy ≥95% while avoiding excessive radiation interference; the signal lines of the sensor module adopt a ground wire wrapping wiring method with a line width of 0.2mm and a ground wire spacing of 0.1mm. The signal is filtered by a ferrite bead before transmission to ensure that the data error is ≤5%; when all expansion modules are working, the power ripple is suppressed by the differential mode inductor and filter capacitor of the power interface, and the final power ripple after expansion is ≤50mV.

[0022] Preferably, in S4, the specific configuration for scene-based mode switching is as follows: For home scene adaptation, the extended PCB is configured with an E1 layer integrating an NFC module, supporting brightness adjustment via mobile phone touch; an E2 layer with a temperature and humidity sensor interface; and the L6 layer of the basic PCB selects a 12V output through a 0Ω resistor to drive two main light sources. For office scene adaptation, the extended PCB is configured with an E1 layer integrating a Bluetooth Mesh module, supporting multi-lamp linkage; an E2 layer with a human body sensor interface, reducing brightness by 50% when no one is present; and the L6 layer of the basic PCB selects a 24V output to drive four light sources. For outdoor walkway scene adaptation, the extended PCB is configured with an E1 layer integrating a lightning protection module; an E2 layer with a photoresistor interface for automatic ambient light adaptation; a wide voltage input on the L5 layer of the basic PCB; and a 48V output on the L6 layer to drive six walkway lights. Switching between the three scenes and other extended scenes only requires replacing the extended PCB, with assembly time ≤ 1 minute, and the basic PCB has 100% universality.

[0023] Preferably, in steps S5 and S6, the multi-module collaboration and interference response mechanism is as follows: when 4 or fewer expansion modules work simultaneously, the MCU prioritizes the allocation of computing power for EMC key algorithms such as PWM spread spectrum and wireless frequency hopping through a task scheduling algorithm, limits the computing power occupation of unnecessary functions, and ensures that the radiated disturbance increment is ≤2dBμV / m and the multi-channel brightness synchronization deviation is ≤±3%; the WiFi module monitors the interference intensity of each channel in real time at a sampling frequency of 0.5Hz, continuously records the interference peak data within 12 hours, automatically selects 3 low-interference channels with interference intensity less than or equal to 70dBm as backups, the channel switching response time is less than or equal to 100ms, and the WiFi communication packet loss rate after switching is less than or equal to 0.8%; the Bluetooth Mesh module supports linkage of 30 lamps, with a communication delay of ≤200ms, and the radiated disturbance increment after shielding is ≤2dBμV / m.

[0024] Preferably, in S7, the fault and emergency protection mechanism is as follows: a self-resetting fuse is connected in series with the power interface of the expansion module. When an overcurrent occurs in the expansion module, it automatically disconnects and automatically resumes conduction after the fault is cleared, thus preventing the PCB and related modules from burning out. When the emergency mode is activated, the MCU automatically reduces the power output of non-essential modules such as Bluetooth and NFC, retaining only the core lighting driver and EMC filtering functions to ensure that conducted interference is ≤40dBμV and radiated interference is ≤32dBμV / m in emergency conditions, complying with GB17743-2017 and EN55015 Class B standards. At the same time, the expansion interface supports hot-swapping, with no reset phenomenon during insertion and removal, and ESD protection and surge protection remain effective, ensuring stable operation of the module.

[0025] Using an 8-layer basic PCB and a 2-layer stackable expansion PCB as the carrier, a wide-voltage AC-CDC power supply, configurable multi-channel drivers, three-mode control + intelligent expansion modules, EMC global filtering network, and hierarchical shielding structure are integrated. The goal is achieved through five-dimensional optimization. The specific solution is as follows:

[0026] Preferably, the multi-layer PCB expansion architecture design uses an 8-layer base PCB to fix the core functions, plus 2 stackable expansion PCBs for flexible adaptation to different scenarios. The detachable architecture retains the original signal, ground, power, and ground signal layers on the base PCB, and the expansion PCBs interface with the base PCB via board-to-board connectors. Specific layering and partitioning are as follows:

[0027] Preferred hierarchical types, number of layers, functional positioning, core expansion, and EMC design considerations:

[0028] The basic PCBL1 low-voltage control area + main shielding cavity includes WiFi / voice, a newly added expansion interface area, 4 sets of board-to-board connector pads with a 2mm pitch, supporting I2C / SPI / UART communication, and TVS diodes and ferrite beads are installed next to the interfaces.

[0029] An independent grounding pad is provided at the corresponding position of the L2 signal ground GND1 expansion interface area, which is connected to the main ground plane through a 0Ω resistor to avoid interference from the expansion module;

[0030] L3 low-voltage power layer, 3.3V / 5V, newly added extended power area, output 3.3V / 5V, with 1A self-resetting fuse to power the expansion module;

[0031] L4 main ground plane GND_MAIN, copper thickness ≥2oz, extended channel ground is connected through a dedicated via, with an independent grounding area to avoid ground loops;

[0032] L5 wide voltage high voltage layer, AC90265V / DC1248V, replacing the original AC220V layer, adopts SY8829 wide voltage PMIC, supports AC and DC input, and is equipped with a 2mm grounding protection strip next to the line.

[0033] L6 can be configured with a multi-channel power layer, 12V / 24V / 48V, divided into 6 independent channels, each with a reserved voltage switching pad, 0Ω resistor selection, and 10μF+0.1μF decoupling capacitor next to each channel;

[0034] L7 power ground GND2 extended channel power ground is independently partitioned and connected to the main ground plane through a 10Ω resistor to suppress extended channel noise;

[0035] The L8 high-voltage power supply area + main EMC filter + 6-channel drive area has a newly added extended channel filter area. Each extended channel has a 10μH differential mode inductor connected in series and a 0.1μF capacitor connected in parallel.

[0036] The stackable and expandable PCBE1 scenario-based expansion module area, such as AI / Bluetooth Mesh / NFC, is equipped with two small shielded sub-cavities, each measuring 10mm×8mm×2mm, which respectively cover the AI ​​and Bluetooth modules. The shielded cavity ground is connected to the main ground through a connector.

[0037] E2 expansion interface and peripheral area, sensor / emergency light interface, layout of 4 sets of standard terminals, JSTPH2.0, corresponding sensor, SHT30, human body sensor, HCSR501, emergency light interface, with ferrite beads next to the terminals.

[0038] Preferred key extensions for EMC collaborative design:

[0039] Detachable connection: The base PCB and expansion PCB are connected by two sets of 10-pin board-to-board connectors with a spacing of 0.5mm and a height of 3mm. The connector pins include power, ground, and communication pins, with the ground pins given priority to ensure good grounding during signal transmission.

[0040] Partition isolation: The horizontal distance between the expansion interface area and the core control area is ≥4mm, and the vertical direction is doubly isolated by L2 signal ground and L4 main ground, so that the noise of the expansion module cannot be coupled to the core control circuit.

[0041] Wide voltage compatibility: The basic PCBL5 layer adopts an ACCDC+DCDC dual-path design. AC90265V is converted to DC12V through SY8829, and DC1248V is directly connected. The two inputs are isolated by diodes to avoid reverse current.

[0042] Standardized expansion interfaces and EMC protection design, expanding without interference core. Three types of standardized interfaces—communication, power, and peripherals—are integrated in the basic PCBL1 layer expansion interface area and the PCBE2 layer peripheral area. Each type of interface has built-in EMC protection components. Specific configuration:

[0043] Preferably, the communication interface supports I2C / SPI / UART:

[0044] Interface type: 4-pin board-to-board connector; I2C: SDA / SCL / GND / VCC; SPI: SCK / MOSI / MISO / GND; pin pitch 2mm.

[0045] EMC protection: Each signal line is connected in series with a 0603 packaged ferrite bead, BLM18PG102SN1D, 1kΩ@100MHz, and in parallel with a 100pF ceramic capacitor, CC0603KRX7R9BB101. The VCC pin is connected in series with a 1A resettable fuse, SMD0805P100TF / 1A, and in parallel with an SMBJ6.5CATVS transistor.

[0046] Power interface, 3.3V / 5V / 12V:

[0047] Output capabilities: 3.3V / 1A, 5V / 1.5A, 12V / 2A, corresponding to different power expansion modules, such as NFC requiring 3.3V / 100mA, and emergency lights requiring 12V / 500mA;

[0048] EMC protection: Each power output has one differential mode inductor (CDRH3D16, 10μH) in series, one 10μF electrolytic capacitor (TAJB106K050RNJ) in parallel, and one 0.1μF ceramic capacitor to suppress power ripple. After expansion, the ripple is ≤50mV.

[0049] Peripheral interfaces, sensors / emergency lights:

[0050] Terminal types: JSTPH2.02Pin, sensor; PH2.04Pin, emergency light; hot-swappable supported.

[0051] EMC protection: A TVS diode, SMBJ6.5CA, and a 100pF filter capacitor are installed next to the terminal pins. The sensor signal line is wrapped with ground wire with a line width of 0.2mm and a ground wire spacing of 0.1mm to reduce external interference coupling.

[0052] The tiered shielding structure design covers both the core module and expansion modules, ensuring comprehensive EMC coverage. Based on the original core module shielding cavity, additional shielding sub-cavities for expansion modules and interface shielding enclosures are added, forming a three-tiered shielding system. Specifically:

[0053] Level 1 shielding, core module: WiFi, ESP32C3, and voice, CI1122 module on the basic PCBL1 layer, using 0.3mm copper foil sidewall + 0.1mm copper cover shielding cavity, size 15mm×12mm×2mm, shielding effectiveness ≥40dB, 30MHz 1GHz;

[0054] Secondary shielding, extended smart module: Extended PCBE1 layer AI module, GD32F450, and Bluetooth Mesh module, CH9121, with two small shielded sub-cavities, measuring 10mm×8mm×2mm, with 0.2mm thick copper foil sidewalls, soldered to the ground plane of the extended PCB through vias, and covered with a 0.1mm copper cap on top, which is in contact with the sidewalls through conductive foam. Shielding effectiveness ≥35dB, 30MHz 1GHz;

[0055] Level 3 shielding for extended interfaces: A 0.3mm thick copper foil dam with a height of 1.5mm is set around the extended interface area of ​​the basic PCBL1 layer. The dam is connected to the L2 signal ground through 4 vias to form an interface shield, suppressing radiation and coupling interference at the interface. The spacing between signal lines inside the dam is ≥0.5mm to avoid crosstalk.

[0056] Preferably, the software extension and EMC collaborative algorithm adapts to the extended functions, maintains anti-interference capabilities, and adds extended module drivers, interference autonomous learning, and multi-module collaborative algorithms to the original PWM spread spectrum, wireless frequency hopping, and ripple compensation algorithms. Specifically:

[0057] Preferred adaptive expansion module drivers: MCU, GD32F103, firmware with built-in expansion module library, supports automatic identification of connected sensors, SHT30, AI module, GD32F450, automatically loads corresponding drivers and filtering parameters, such as sensor sampling frequency adaptation to 1kHz, to avoid resonance with PWM frequency;

[0058] Preferred interference self-learning algorithm: The WiFi module monitors the interference intensity of each channel in real time, with a sampling frequency of 0.5Hz, records the interference peak value within 12 hours, automatically selects 3 low-interference channels with interference intensity ≤70dBm as backups, switching response time ≤100ms, and communication packet loss rate ≤0.8%; Multi-module EMC collaboration: When expansion modules, such as AI, and core modules, such as voice, work simultaneously, the MCU dynamically adjusts the PWM spread spectrum period from 10ms to 8ms, and allocates computing power with the AI ​​module to prioritize the operation of key EMC algorithms, avoiding EMI superposition caused by multiple modules working simultaneously, with radiated interference increment ≤2dBμV / m;

[0059] Preferred emergency mode EMC protection: When the emergency lighting module is activated, if there is a power failure, the MCU automatically reduces the power of non-essential modules, such as Bluetooth, and retains only the core lighting and EMC filtering functions to ensure that conducted interference is ≤40dBμV in emergency situations.

[0060] The preferred approach is to use scenario-specific hardware design, where a single board covers multiple scenarios. By expanding PCB selection and configuring the basic PCB, different scenarios can be adapted without redesigning the basic PCB.

[0061] For home use, 12V / 2-channel driver + NFC configuration: The extended PCBE1 layer integrates a PN532 NFC module, which supports brightness configuration by mobile phone touch. The E2 layer is equipped with an SHT30 temperature and humidity sensor interface. The basic PCBL6 layer selects the 12V output through a 0Ω resistor to drive 2 main light sources.

[0062] For office scenarios, 24V / 4-channel driver + Bluetooth Mesh: The extended PCBE1 layer integrates the CH9121 Bluetooth Mesh module, which supports the linkage of 10 lamps. The E2 layer is equipped with an HCSR501 human body sensor interface, which reduces the brightness by 50% when no one is present. The basic PCBL6 layer selects 24V output to drive 4 light sources, including the main light and auxiliary light.

[0063] Preferred outdoor walkway scenario, 48V / 6-channel driver + wide voltage input: Extended PCE1 layer integrates a surge protection module with TVS diode SMBJ48CA, E2 layer has a photoresistor interface to automatically adapt to ambient light, basic PCL5 layer connects to DC1248V wide voltage input, L6 layer selects 48V output to drive 6 walkway lights.

[0064] Compared with the prior art, the beneficial effects of the present invention are:

[0065] 1. The EMC performance of this invention consistently meets the standards: both conducted and radiated disturbances after expansion comply with relevant mandatory certification standards, exhibiting excellent anti-interference capabilities and resisting external interference such as electrostatic discharge and surges. There are no abnormal resets during the hot-plugging of the expansion interface, and stable electromagnetic compatibility performance is maintained throughout the process.

[0066] 2. The scalability and scene adaptability of this invention are significantly improved: It supports the expansion of multiple functional modules such as environmental sensing, human body sensing, intelligent dimming, and emergency lighting, achieving plug-and-play functionality; Through the combination of the basic PCB and different expansion PCBs, it can be flexibly adapted to various application scenarios such as home, office, and outdoor use, without the need for new mold development; The expansion interface is compatible with common communication protocols and can be adapted to mainstream sensors and smart modules on the market, without the need for customized development.

[0067] 3. The cost increase brought about by the expansion of related hardware components is limited, and the overall cost control is reasonable. The base PCB and the expansion PCB can be produced independently and combined and assembled as needed according to actual requirements, which effectively shortens the production cycle, reduces the pressure of inventory backlog, and takes into account both high integration and production economy.

[0068] 4. This invention has a wealth of intelligent functions such as AI, adaptive dimming, Bluetooth, Mesh, and multi-lamp linkage. The dimming and networking response is sensitive and the effect is accurate. After expansion, the device operates stably, the power output is smooth, the brightness of multiple channels is consistent, and the wireless communication and voice recognition can maintain reliable performance in complex electromagnetic environments, with outstanding anti-interference ability. Attached Figure Description

[0069] Figure 1 The present invention provides an operational flow diagram of an integrated PCB module and control method for a street light that combines EMC anti-interference performance with high scalability. Figure 1 ;

[0070] Figure 2 The present invention provides an operational flow diagram of an integrated PCB module and control method for a street light that combines EMC anti-interference performance with high scalability. Figure 2 ;

[0071] Figure 3 The present invention provides an operational flow diagram of an integrated PCB module and control method for a street light that combines EMC anti-interference performance with high scalability. Figure 3 ;

[0072] Figure 4 The present invention provides an operational flow diagram of an integrated PCB module and control method for a street light that combines EMC anti-interference performance with high scalability. Figure 4 . Detailed Implementation

[0073] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0074] Example

[0075] Please see Figures 1-4 As shown, the present invention provides a technical solution: the PCB module includes an 8-layer basic PCB, a 2-layer stackable expansion PCB, and board-to-board connectors, and the control method includes the following steps:

[0076] S1. After the PCB module is powered on, the SY8829 wide voltage PMIC on the basic PCB starts to adapt to wide voltage input. The MCU initializes the expansion module library and automatically identifies the connected AI, Bluetooth Mesh, sensor and other expansion modules, and loads the corresponding drivers.

[0077] S2, the global EMC filtering network starts up simultaneously, using the common mode inductor and X / Y capacitor of the basic PCB, the ferrite beads, TVS tubes and hierarchical shielding structure of the extended interface to suppress power grid interference, interface interference and radiation interference in multiple dimensions.

[0078] S3. When the extended function is running, the MCU dynamically adjusts parameters such as PWM spread frequency period and computing power allocation to achieve coordinated adaptation between the extended function and EMC performance.

[0079] S4. Depending on the application scenarios such as home, office, and outdoor, mode switching can be completed simply by replacing the appropriate expansion PCB, without the need to redesign the basic PCB.

[0080] S5. When multiple expansion modules work simultaneously, the MCU prioritizes allocating computing power to key EMC algorithms such as PWM spread spectrum and wireless frequency hopping to avoid EMI superposition.

[0081] S6. The wireless communication module monitors the channel interference intensity in real time and automatically switches to a low-interference backup channel to ensure communication stability.

[0082] S7. When a module overcurrent fault or emergency lighting requirement occurs, the corresponding protection mechanism will be activated to ensure that the core functions and EMC performance continue to meet the standards.

[0083] In this embodiment, the 8-layer base PCB is stacked in the order of signal-ground-power-ground-signal-power-ground-signal, and is divided into a high-voltage power supply area, a low-voltage control area, a wireless communication area, a 6-channel configurable driver area, and an expansion interface area. The expansion interface area has reserved 4 sets of board-to-board connector pads, and ferrite beads, self-resetting fuses, and TVS diodes are provided next to the interfaces. The 2-layer stackable expansion PCB includes an expansion module area and a peripheral interface area. The expansion module area has 2 shielded sub-cavities, and the peripheral interface area is laid out with JSTPH2.0 terminals. The board-to-board connector is 10-pin, with ground pins given priority. The L4 layer of the base PCB is the main ground plane with a copper thickness of ≥2oz. The expansion channel ground and signal ground are connected through independent vias, and the ground loop impedance is ≤1Ω.

[0084] In this embodiment, the L5 layer of the 8-layer basic PCB is a wide-voltage high-voltage layer, adopting an ACCDC+DCDC dual-path design. The AC input is converted to DC12V through the SY8829 wide-voltage PMIC, and DC12-48V is directly connected. The two inputs are isolated by diodes to avoid circuit damage. The L6 layer is a 6-channel configurable power supply layer, with a reserved 0Ω resistor voltage switching pad for each channel. The 12V, 24V, and 48V output voltages can be flexibly adapted by soldering 0Ω resistors. Each channel is connected in parallel with a 10μF electrolytic capacitor and a 0.1μF ceramic capacitor to form a decoupling circuit to suppress power ripple and ensure drive stability.

[0085] In this embodiment, the E1 layer of the two stackable expandable PCB has two shielding sub-cavities with dimensions of 10mm×8mm×2mm, which respectively cover the AI ​​module and the Bluetooth Mesh module. The sidewalls of the shielding sub-cavities are made of 0.2mm thick copper foil, which is soldered to the ground plane of the E2 layer through vias. The top is covered with a 0.1mm thick copper cap, which is in contact with the sidewalls through conductive foam to ensure shielding effectiveness ≥35dB. The E2 layer is laid with JSTPH2.0 series terminals, including 2-pin terminals and 4-pin terminals, which are respectively adapted to the temperature and humidity sensor and the emergency lighting module. TVS diodes and 100pF filter capacitors are connected in parallel next to each terminal to suppress electrostatic and electromagnetic coupling interference.

[0086] In this embodiment, the horizontal distance between the expansion interface area and the core control area of ​​the basic PCB is greater than or equal to a preset threshold of ≥4mm. In the vertical direction, double isolation is achieved through the L2 signal ground and the L4 main ground plane to prevent noise from the expansion module from coupling to the core control circuit. A 0.3mm thick copper foil shielding dam is provided around the expansion interface area, with a dam height of 1.5mm. It is connected to the L2 signal ground through four evenly distributed vias to form a closed interface shield. The signal line spacing inside the dam is ≥0.5mm to further suppress crosstalk between signal lines.

[0087] In this embodiment, in step S1, the MCU model is GD32F103, and its firmware has a complete built-in expansion module library. The types of expansion modules that can be automatically identified include lightweight AI modules, Bluetooth Mesh modules, NFC configuration modules, temperature and humidity sensors, human body sensing modules, emergency lighting modules, etc. The identification process is achieved by detecting the communication pin signal characteristics of the expansion interface. The identification response time is ≤50ms. After successful identification, the corresponding driver program and filtering parameters are automatically loaded, such as the sensor sampling frequency is adapted to 1kHz to avoid interference caused by resonance with the PWM drive frequency.

[0088] In this embodiment, the full-area EMC filtering network in S2 is specifically configured as follows: the L8 layer of the basic PCB integrates a 10mH common-mode inductor, a 0.1μFX capacitor, and a 2200pFY capacitor to suppress conducted interference on the power grid side; each signal line in the extended interface area is connected in series with a ferrite bead to suppress high-frequency signal interference; the TVS diode next to the peripheral terminal on the E2 layer of the extended PCB can withstand ±15kV air discharge and ±8kV contact discharge to prevent electrostatic damage to the module; the hierarchical shielding structure includes primary shielding, secondary shielding, and tertiary shielding. The primary shielding is the shielding cavity of the core WiFi / voice module with a shielding effectiveness ≥40dB; the secondary shielding is the shielding sub-cavity of the extended AI / Bluetooth module; and the tertiary shielding is the dam around the extended interface, achieving full-area EMC protection without dead angles.

[0089] In this embodiment, the implementation of the expansion function and EMC coordination in S3 is as follows: When the AI ​​module runs the adaptive dimming algorithm, the MCU dynamically adjusts the PWM spread frequency period from the basic 10ms to 8ms according to the computing power occupancy of the AI ​​module, ensuring dimming accuracy ≥95% while avoiding excessive radiation interference; the signal lines of the sensor module adopt a ground wire wrapping wiring method with a line width of 0.2mm and a ground wire spacing of 0.1mm. The signal is filtered by a ferrite bead before transmission to ensure that the data error is ≤5%; when all expansion modules are working, the power ripple is suppressed by the differential mode inductor and filter capacitor of the power interface, and the final power ripple after expansion is ≤50mV.

[0090] In this embodiment, the specific configuration for scene-based mode switching in S4 is as follows: For the home scene, the extended PCB is configured with an E1 layer integrating an NFC module, supporting brightness adjustment via mobile phone touch, an E2 layer with a temperature and humidity sensor interface, and the L6 layer of the basic PCB using a 0Ω resistor to select 12V output to drive two main light sources; for the office scene, the extended PCB is configured with an E1 layer integrating a Bluetooth Mesh module, supporting multi-lamp linkage, an E2 layer with a human body sensor interface, reducing brightness by 50% when no one is present, and the L6 layer of the basic PCB using a 24V output to drive four light sources; for the outdoor walkway scene, the extended PCB is configured with an E1 layer integrating a lightning protection module, an E2 layer with a photoresistor interface for automatic ambient light adaptation, the L5 layer of the basic PCB connected to a wide voltage input, and the L6 layer using a 48V output to drive six walkway lights. Switching between these three scenes and other extended scenes only requires replacing the extended PCB, with assembly time ≤ 1 minute, and the basic PCB has 100% compatibility.

[0091] In this embodiment, the multi-module collaboration and interference response mechanism in steps S5 and S6 is as follows: When 4 or fewer expansion modules work simultaneously, the MCU prioritizes the allocation of computing power for EMC key algorithms such as PWM spread spectrum and wireless frequency hopping through a task scheduling algorithm, limits the computing power occupation of unnecessary functions, and ensures that the radiated disturbance increment is ≤2dBμV / m and the multi-channel brightness synchronization deviation is ≤±3%; the WiFi module monitors the interference intensity of each channel in real time at a sampling frequency of 0.5Hz, continuously records the interference peak data within 12 hours, automatically selects 3 low-interference channels with interference intensity less than or equal to 70dBm as backups, the channel switching response time is less than or equal to 100ms, and the WiFi communication packet loss rate after switching is less than or equal to 0.8%; the Bluetooth Mesh module supports linkage of 30 lamps, with a communication delay of ≤200ms, and the radiated disturbance increment after shielding is ≤2dBμV / m.

[0092] In this embodiment, the fault and emergency protection mechanism in S7 is as follows: a self-resetting fuse is connected in series with the power interface of the expansion module. When an overcurrent occurs in the expansion module, it automatically disconnects and automatically resumes conduction after the fault is cleared, thus preventing the PCB and related modules from being burned out. When the emergency mode is activated, the MCU automatically reduces the power output of non-essential modules such as Bluetooth and NFC, retaining only the core lighting driver and EMC filtering functions to ensure that conducted interference is ≤40dBμV and radiated interference is ≤32dBμV / m in emergency conditions, which complies with GB17743-2017 and EN55015 Class B standards. At the same time, the expansion interface supports hot-swapping, and there is no reset phenomenon during the insertion and removal process. ESD protection and surge protection remain effective, ensuring stable operation of the module.

[0093] In this embodiment, the core component list (including extended and EMC collaborative components) is as follows:

[0094] Component Category | Component Name | Model | Specifications | Quantity | Unit Price (RMB) | Core Function | Expansion + EMC;

[0095] The expansion architecture component board-to-board connector is 10-pin with a pitch of 0.5mm and a height of 3mm. The base PCB and expansion PCB are detachably connected, with ground pins prioritized.

[0096] Extended PCB shielding sub-cavity copper cover with 0.1mm thick copper foil (10mm×8mm×2mm) 20.3 shielding AI / Bluetooth module, radiated interference ≤35dBμV / m;

[0097] The expansion interface is protected by a self-resetting fuse SMD0805P100TF / 1A40.4, which provides overcurrent protection for the expansion power supply to prevent module burnout.

[0098] Signal bead BLM18PG102SN1D (1kΩ@100MHz) 80.8 suppresses high-frequency interference on extended signal lines;

[0099] The wide-voltage and drive-wide-voltage PMICSY8829 (AC90265V / DC1248V) 13.5 supports multi-scenario voltage input, replacing the original fixed-voltage PMIC;

[0100] The CDRH3D16 (10μH) 61.8 differential-mode inductor for extended channels suppresses differential-mode interference in 6 extended channels;

[0101] The intelligent expansion module AI module GD32F450 (lightweight MCU, supports dimming algorithm) 15.2 realizes AI adaptive dimming and is integrated into the shielded sub-cavity;

[0102] The CH9121 Bluetooth Mesh module (supports 2.4GHz Mesh networking) features multi-LED linkage and, after shielding, radiated interference increment ≤2dBμV / m.

[0103] Emergency and sensor-based emergency light interface terminal JSTPH2.04Pin10.2 for emergency lighting module docking, with a TVS tube next to the terminal;

[0104] The SHT3012.5 temperature and humidity sensor acquires ambient temperature and humidity data; the signal cable features a ferrite bead filter.

[0105] Subtotal of expansion components 20.3 includes core components for EMC protection and scenario-based expansion.

[0106] In this embodiment, the PCB fabrication and assembly process includes an extension module:

[0107] PCB fabrication: Basic PCB: FR4 substrate, dielectric constant 4.4, total thickness 1.6mm, L4 main ground plane copper thickness 2oz, expansion interface area reserved connector pads and shielding dam; Expansion PCB: FR4 substrate, total thickness 0.8mm, E1 layer etched shielding sub-cavity sidewall, 0.2mm copper foil, E2 layer layout of peripheral terminals, positioned with board-to-board connectors to the basic PCB;

[0108] Surface treatment: Both the base PCB and the expansion PCB adopt the electroless gold process to ensure the conductivity of the shielding cavity and the reliability of soldering.

[0109] Component assembly (in stages):

[0110] Phase 1, Basic PCB Core Components: Mounting ACDC power supply, SY8829, main EMC filter components (common mode inductor / XY capacitor / TVS tube), core control module (MCU / WiFi / voice), and soldering the copper cover of the main shielding cavity;

[0111] Phase 2, Basic PCB Expansion Interfaces: Surface mount board-to-board connectors, expansion interface protection components, ferrite beads / fuses / TVS tubes, and soldered expansion interface shielding barriers;

[0112] Phase 3, Expanding PCB: Mounting scenario-specific modules, such as PN532 for home use and CH9121 for office use, peripheral terminals, and soldering shielded sub-cavity copper covers;

[0113] Phase 4, Assembly: Connect the expansion PCB to the base PCB via board-to-board connectors, press until the latches are locked. If the assembly time is ≤1 minute, check the interface continuity. If there are no loose connections.

[0114] EMC and Extended Functionality Joint Testing:

[0115] Extended EMC testing: According to GB17743-2017, conducted emissions (30MHz-1GHz ≤ 40dBμV), radiated emissions (30MHz-1GHz ≤ 32dBμV / m), and ESD ±15kV air discharge without fault; Extended function testing: In home scenarios, NFC configuration is tested, such as a touch success rate of ≥98%; in office scenarios, Bluetooth Mesh linkage is tested, such as synchronous dimming deviation of 10 lamps ≤ ±2%; in outdoor scenarios, wide voltage input is tested (brightness is stable when inputting 1248V).

[0116] Stability test: After 72 hours of continuous operation, with the addition of 4 modules, the power ripple (≤50mV), WiFi packet loss rate (≤0.8%), and AI dimming accuracy (≥95%) were monitored, and no functional abnormalities were found.

[0117] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their likenesses.

[0118] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A street light integrated PCB module and control method that combines EMC anti-interference performance with high scalability, characterized in that, The PCB module includes an 8-layer base PCB, a 2-layer stackable expansion PCB, and board-to-board connectors. The control method includes the following steps: S1. After the PCB module is powered on, the SY8829 wide voltage PMIC on the basic PCB starts to adapt to wide voltage input. The MCU initializes the expansion module library and automatically identifies the connected AI, Bluetooth Mesh, and sensor expansion modules, and loads the corresponding drivers. S2, the global EMC filtering network starts up simultaneously, using the common mode inductor and X / Y capacitor of the basic PCB, the ferrite beads, TVS tubes and hierarchical shielding structure of the extended interface to suppress power grid interference, interface interference and radiation interference in multiple dimensions. S3. When the extended function is running, the MCU dynamically adjusts parameters such as PWM spread frequency period and computing power allocation to achieve coordinated adaptation between the extended function and EMC performance. S4. Depending on the application scenario, mode switching can be completed simply by replacing the compatible expansion PCB; the basic PCB does not need to be redesigned. S5. When multiple expansion modules are working simultaneously, the MCU prioritizes allocating computing power to PWM spread spectrum and wireless frequency hopping EMC key algorithms. S6. The wireless communication module monitors the channel interference intensity in real time and automatically switches to a low-interference backup channel to ensure communication stability. S7. When a module overcurrent fault occurs or an emergency lighting requirement is needed, the corresponding protection mechanism will be activated.

2. The integrated PCB module and control method for a street light that combines EMC anti-interference performance and high scalability according to claim 1, characterized in that: The L5 layer of the 8-layer basic PCB is a wide-voltage high-voltage layer, adopting an AC-CDC+DCDC dual-path design. The AC input is converted to DC12V through the SY8829 wide-voltage PMIC, and DC12-48V can be directly connected. The two inputs are isolated from each other by diodes. The L6 layer is a 6-channel configurable power supply layer, with a reserved 0Ω resistor voltage switching pad for each channel. The 12V, 24V, and 48V output voltages can be flexibly adapted by soldering 0Ω resistors. Each channel is connected in parallel with a 10μF electrolytic capacitor and a 0.1μF ceramic capacitor to form a decoupling circuit to suppress power supply ripple.

3. The integrated PCB module and control method for a street light that combines EMC anti-interference performance and high scalability according to claim 2, characterized in that: The E1 layer of the two-layer stackable expandable PCB has two shielded sub-cavities of different sizes, which respectively cover the AI ​​module and the Bluetooth Mesh module. They are fixed to the ground plane of the E2 layer through vias. The top is covered with a 0.1mm thick copper cap, which contacts the sidewalls through conductive foam. The E2 layer is laid with JSTPH2.0 series terminals, including 2-pin terminals and 4-pin terminals, which are respectively adapted to the temperature and humidity sensor and the emergency lighting module. TVS diodes and 100pF filter capacitors are connected in parallel next to each terminal to suppress electrostatic and electromagnetic coupling interference.

4. The integrated PCB module and control method for a street light that combines EMC anti-interference performance and high scalability according to claim 3, characterized in that: The horizontal distance between the expansion interface area and the core control area of ​​the basic PCB is greater than or equal to a preset threshold. In the vertical direction, double isolation is achieved through the L2 signal ground and the L4 main ground plane to prevent noise from the expansion module from coupling to the core control circuit. A copper foil shielding dam is provided around the expansion interface area, which is connected to the L2 signal ground through four evenly distributed vias to form a closed interface shield.

5. The integrated PCB module and control method for a street light that combines EMC anti-interference performance and high scalability according to claim 4, characterized in that: In S1, the MCU firmware has a built-in complete expansion module library, which supports automatic identification of expansion module types including lightweight AI modules, Bluetooth Mesh modules, NFC configuration modules, temperature and humidity sensors, human body sensing modules, emergency lighting modules, etc. The identification process is achieved by detecting the communication pin signal characteristics of the expansion interface. After successful identification, the corresponding driver and filtering parameters are automatically loaded.

6. The integrated PCB module and control method for a street light that combines EMC anti-interference performance and high scalability according to claim 5, characterized in that: In S2, the global EMC filtering network is specifically configured as follows: the L8 layer of the basic PCB integrates a 10mH common-mode inductor, a 0.1μFX capacitor, and a 2200pFY capacitor to suppress conducted interference on the power grid side; each signal line in the extended interface area is connected in series with a ferrite bead to suppress high-frequency signal interference; the TVS diode next to the peripheral terminal on the E2 layer of the extended PCB can withstand ±15kV air discharge and ±8kV contact discharge; the hierarchical shielding structure includes primary shielding, secondary shielding, and tertiary shielding. The primary shielding is the shielding cavity of the core WiFi / voice module, the secondary shielding is the shielding sub-cavity of the extended AI / Bluetooth module, and the tertiary shielding is the dam of the extended interface.

7. The integrated PCB module and control method for a street light that combines EMC anti-interference performance and high scalability according to claim 6, characterized in that: In S3, the implementation of the expansion function and EMC coordination is as follows: when the AI ​​module runs the adaptive dimming algorithm, the MCU dynamically adjusts the PWM spread frequency period from the basic 10ms to 8ms according to the computing power occupancy of the AI ​​module; the signal lines of the sensor module adopt the ground wire wrapped wiring method, and the signal is filtered by ferrite beads before transmission; when all expansion modules are working, the power ripple is suppressed by the differential mode inductor and filter capacitor of the power interface.

8. The integrated PCB module and control method for a street light that combines EMC anti-interference performance and high scalability according to claim 7, characterized in that: In S4, the specific configuration for scene-based mode switching is as follows: the extended PCB for home scene adaptation is configured with an NFC module integrated on the E1 layer, a temperature and humidity sensor interface on the E2 layer, and the L6 layer of the basic PCB selects a 12V output through a 0Ω resistor to drive two main light sources. The extended PCB configuration adapted for office scenarios has a Bluetooth Mesh module integrated on the E1 layer, a human body sensing interface on the E2 layer, and a brightness reduction of 50% when no one is present. The L6 layer of the basic PCB is selected to output 24V to drive 4 light sources. The expansion PCB for outdoor walkway scenarios is configured with an integrated surge protection module on the E1 layer, a photoresistor interface on the E2 layer for automatic ambient light adaptation, a wide voltage input on the L5 layer of the basic PCB, and a 48V output on the L6 layer to drive 6 walkway lights. Switching between the three scenarios and other expansion scenarios only requires replacing the expansion PCB.

9. The integrated PCB module and control method for a street light that combines EMC anti-interference performance and high scalability according to claim 8, characterized in that: In steps S5 and S6, the multi-module collaboration and interference response mechanism is as follows: when 4 or fewer extension modules work simultaneously, the MCU prioritizes the allocation of computing power for the PWM spread spectrum and wireless frequency hopping EMC key algorithms through a task scheduling algorithm; the WiFi module monitors the interference intensity of each channel in real time at a sampling frequency of 0.5Hz, continuously records the interference peak data, and automatically selects 3 low-interference channels with interference intensity less than or equal to 70dBm as backups.

10. The integrated PCB module and control method for a street light that combines EMC anti-interference performance and high scalability according to claim 9, characterized in that: In S7, the fault and emergency protection mechanism is as follows: the power interface of the expansion module is connected in series with a self-resetting fuse, which automatically disconnects when the expansion module experiences an overcurrent and automatically resumes conduction after the fault is cleared; when the emergency mode is activated, the MCU automatically reduces the power output of non-essential modules such as Bluetooth and NFC, retaining only the core lighting driver and EMC filtering functions; at the same time, the expansion interface supports hot-swapping, with no reset phenomenon during the plugging and unplugging process, and ESD protection and surge protection remain effective.

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